[obs.] A terminal that has a display screen but which, because of
hardware or software limitations, behaves like a teletype or some other
printing terminal, thereby combining the disadvantages of both: like a
printing terminal, it can't do fancy display hacks, and like a display
terminal, it doesn't produce hard copy. An example is the early
‘dumb’ version of Lear-Siegler ADM 3 (without cursor control).
See tube, tty; compare
dumb terminal. See TV Typewriters (Appendix A) for
an interesting true story about a glass tty.